//
//  rng.h
//
//  Created by Bassham, Lawrence E (Fed) on 8/29/17.
//  Copyright © 2017 Bassham, Lawrence E (Fed). All rights reserved.
//

#ifndef rng_h
#define rng_h

#include <stdio.h>

#define RNG_SUCCESS 0
#define RNG_BAD_MAXLEN -1
#define RNG_BAD_OUTBUF -2
#define RNG_BAD_REQ_LEN -3

typedef struct {
	unsigned char buffer[16];
	int buffer_pos;
	unsigned long length_remaining;
	unsigned char key[32];
	unsigned char ctr[16];
} AES_XOF_struct;

typedef struct {
	unsigned char Key[32];
	unsigned char V[16];
	int reseed_counter;
} AES256_CTR_DRBG_struct;

void AES256_CTR_DRBG_Update(unsigned char *provided_data,
                            unsigned char *Key,
                            unsigned char *V);

int seedexpander_init(AES_XOF_struct *ctx,
                      unsigned char *seed,
                      unsigned char *diversifier,
                      unsigned long maxlen);

int seedexpander(AES_XOF_struct *ctx, unsigned char *x, unsigned long xlen);

void randombytes_init(unsigned char *entropy_input,
                      unsigned char *personalization_string,
                      int security_strength);

int randombytes(unsigned char *x, unsigned long long xlen);

#endif /* rng_h */
